Technical University Braunschweig - Computer Science - Operating Systems and Computer Networks

The term authentication is used to describe the proof of a claimed identity. This project deals with the analysis of properties of authentication protocols.

Based on the analysis of the Kerberos protocol, we suggested a nonce based protocol which does not rely on synchronized clocks. An analysis with the BAN logic (named after their authors M. Burrows, M. Abadi and R. Needham) proves the correctness of our protocol.

In this protocol two principals A and B, not sharing any secret, want to authenticate each other. A trusted authentication server S shares a secret key with each principal. Since no timestamps relying on synchronized clocks are used in this protocol, the freshness of the messages is achieved with nonces, which are a kind of once used keys.

• A. Kehne, J. Schönwälder, H. Langendörfer:
  Multiple Authentications with a Nonce-Based Protocol Using Generalized Timestamps
  Proc. International Conference on Computer Communication '92, Genua, 1992.

• A. Kehne, J. Schönwälder, H. Langendörfer:
  A Nonce-Based Protocol for Multiple Authentications
  Operating System Review, 26(4), October 1992.